Embodiments of the present disclosure relate to wind energy conversion devices, and more particularly to electro-hydrodynamic wind energy conversion devices.
Traditional wind energy conversion devices like wind turbines include multiple mechanical rotating or moving parts such as rotor blades, shafts, generators, gearboxes, brakes, and the like. Wind impinging on the blades causes the blades to rotate. This rotation is converted into electrical energy by a generator that is coupled to the blades. Although these wind turbines have proved to be highly successful in onshore and offshore windy regions, they require expensive parts and are often viewed as unaesthetic objects. Moreover, as the mechanical wind turbines include noisy rotating and moving parts, they are unsuitable for certain areas.
Recently, as an alternative to the mechanical wind turbines, wind energy conversion devices that work on the principles of electro-hydrodynamics (EHD) have been developed. These devices do not generate electricity through the motion of any moving parts; instead, they generate electricity by generating small electrically charged liquid droplets and/or solid particles and introducing them into the wind path. The wind carries the charged droplets and/or particles towards a collection grid, where the electric charge of the droplets is deposited. In these systems, the wind speed determines the number of liquid droplets and/or solid particles carried away from the injection point per unit time, and therefore the amount of electrical energy generated by the device. These EHD wind energy conversion devices are capable of generating electricity akin to the mechanical wind turbines without the added noise or moving parts. Moreover, these devices are inexpensive, aesthetically more pleasing, and simple to construct.
Existing EHD wind energy conversion devices, however, may not be very efficient. Current technologies use a nozzle or electrospray to convert a liquid into charged droplets. In these technologies, water is pressurized and sprayed out of a point source to form droplets. However, as the nozzles are point sources, they may not be able to produce a large number of droplets or droplets having small dimensions optimal for EHD power conversion. The number and size of droplets are important factors affecting the efficiency of these devices as these factors directly affect the cumulative power generated by the device. For example, if the drops are too large, the drag force of low speed winds may be insufficient to carry the droplets effectively, and if the number of droplets is too low, it may lead to lower power generation.